Device for the continuous prebending, particularly, of hot-rolled pipes

ABSTRACT

A DEVICE FOR THE CONTINUOUS PREBENDING, PARTICULARLY, OF HOT-ROLLED PIPES WHICH ARE TO BE WOUND ON A SUBSEQUENT DEVICE, INCLUDES A MULTI-ROLL SYSTEM HAVING A COMMON DRIVE WHICH IS COUPLED WITH THE SUPPORTING FRAME OF THE DEVICE. THE SUPPORTING FRAME MOUNTS A MAGAZINE CONTAINING A PLURALITY OF BENDING AND CALIBRATING ROLLS ARRANGED IN PAIRS FOR BENDING A PIPE PASSED THEREBETWEEN. THE MAGAZINE IS SLIDABLY MOUNTED ON THE FRAME SO IT MAY BE SHIFTED ALONG THE FRAME. ONE COOPERATING PAIR OF A CALIBRATING ROLLER AND A BENDING ROLLER IS MOUNTED ON A MOVABLE HOLDER OF THE MAGAZINE. THE HOLDER IS PIVOTALLY MOUNTED THAT IT WILL BE SHIFTED TO VARY THE BENDING CURVE RADIUS OF OPERATION OF THE ROLLERS IN ACCORDANCE WITH THE SHIFTING MOVEMENT OF THE MAGAZINE ON THE FRAME. TO ACCOMPLISH THIS, THE HOLDER IS CONNECTED TO A LEVER HAVING A ROLLER WHICH IS CONFINED IN A SLOT DEFINED ON THE FRAME.

March 16, 1971 G 3 ETAL v DEVICE FOR THE CONTINUOUS PREBENDING.

PARTICULARLY, 0F HOT-ROLLED PIPES I Filed June 2,

Inventors Gm/M20 STECK M4 N5 'a/erefl WE/TERMAMV A Tram/5 y;

United States Patent O 3,570,292 DEVICE FOR THE CONTINUOUS PREBENDING,

PARTICULARLY, F HOT-ROLLED PIPES Gerhard Steck, Rheinhausen, andHans-Dieter Weltermann, Duisburg, Germany, assignors to DemagAktiengesellschaft, Duisburg, Germany Filed June 2, 1969, Ser. No.829,483 Claims priority, application Germany, June 7, 1968, P 17 52506.3 Int. Cl. B21d 7/08 U.S. Cl. 72173 6 Claims ABSTRACT OF THEDISCLOSURE A device for the continuous prebending, particularly, ofhot-rolled pipes which are to be wound on a subsequent device, includesa multi-roll system having a common drive which is coupled with thesupporting frame of the device. The supporting frame mounts a magazinecontaining a plurality of bending and calibrating rolls arranged inpairs for bending a pipe passed therebetween. The magazine is slidablymounted on the frame so it may be shifted along the frame. Onecooperating pair of a calibrating roller and a bending roller is mountedon a movable holder of the magazine. The holder is pivotally mounted sothat it will be shifted to vary the bending curve radius of operation ofthe rollers in accordance with the shifting movement of the magazine onthe frame. To accomplish this, the holder is connected to a lever havinga roller which is confined in a slot defined on the frame.

SUMMARY OF THE INVENTION This invention relates in general to theconstruction of devices for forming piping and in particular to a newand useful device for pre-bending rolled pipes in a hot condition andwhich includes a shiftable magazine which is mounted on a supportingframe and which includes a plurality of bending and calibrating rollers,one set of which is mounted so as to be shifted in orientation duringthe shifting of the magazine to accommodate various sized pipes.

The present invention is an improvement over application, Ser. No.782,282, filed on Dec. 9, 1968, by the inventor of the present case,particularly in respect to the mounting of a set of a single bending anda single calibrating roller on a pivotal holder contained on magazinestructure such that the pipe may be wound into spiral layers which arearranged in exact superposition. The device permits the pre-bending andwinding of relatively large calibrated pipes when they are in the rolledhot state. The bending roll magazine includes an inlet side carrying abending roller and a spaced apart bending roller and calibrating rollerset. The outlet end includes a bending and calibrating roller set whichare mounted on the pivotal holder. The holder is controlled in itsposition by a fulcrum which is actuated by the action of a cam slot on aroller which is confined in the slot. The cam slot is defined on asupporting frame and when the magazine is moved relative to the frame,the roller is shifted to shift the lever to accurately position theholder in accordance with the cam outline control. Thus, the shifting ofthe magazine on its supporting base permits automatic adjustment of themagazine and the rollers thereon to accommodate the various sizes ofpipe which are to be bent and to accommodate the selected bendingradius.

With the construction, the last roll group is provided with the specialadjusting means which can be adapted within Wide limits to the selectedbending and winding radius. The guide roller which controls the pivotalmounting of the holder for the last roller group is advantageouslyconfined in a substantially U-shaped slot of the guide cam Patented Mar.16, 1971 which is carried on the supporting base. The guide cam isadvantageously made so that it can be exchanged with an other guidehaving a different motion characteristic.

In addition to the fact that the device provides an extremely simple,safe and inexpensive construction of a pipe bending device, a particularadvantage in the construction is that it permits precision winding, thatis, all spiral layers of the wound pipe will have substantially the sameradii and thus they can be exactly superposed. This advantage becomesparticularly manifest if, for eX- ample, in the manufacture of coolingand heating coils, a predetermined number of turns for a correspondinglength of pipe has to be produced without requiring subsequentdeformation of the bent pipe.

A further advantage of the construction is that the carriage is mountedon a supporting base so that it can be moved over the entire width ofthe winding cage and the correct, or desired, bending radius can alwaysbe set in the range of the cage width in any position of the bendingmachine. Because the guide rail may be exchanged to provide one ofdifferent geometric form, the bending radius can be adapted in anextremely simple and rapid manner to the new operating requirements, forexample, to pipes which may have smaller bending radii than thepreceding ones.

Accordingly, it is an object of the invention to provide an improvedbending machine which includes a magazine which is mounted on thesupporting frame for movement therewith and wherein the last one of agroup of sets of bending and calibrating rollers is mounted on a holderwhich may be shifted in accordance with the movement of the magazine onthe frame.

A further object of the invention is to provide a bending device, whichis simple in design, rugged in construction and economical tomanufacture.

The various features of novelty which characterize the invention arepointed out with particularity in the claims annexed to and forming apart of this specification. For a better understanding of the invention,its operating advantages and specific objects attained by its use,reference should be had to the accompanying drawings and descriptivematter in which there is illustrated and described a preferredembodiment of the invention.

BRIEF DESCRIPTION OF THE DRAWING The only figure of the drawing is ahorizontal sectional view of a portion of a bending machine constructedin accordance with the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to thedrawing, in particular, the invention embodied therein includes abending machine having a magazine generally designated 1 which isslidable on a mounting base or frame 4. The magazine carries bendingrolls or rollers 2 and 2a which are adapted to be arranged on respectivesides of a pipe which is fed in the direction of arrows 10 and which arelocated at the entrance end of the device. A guide or hopper 12 islocated between bending rollers 2 and 2a and, in addition, a calibratingroller 3 is arranged directly adjacent the roller 2a for cooperatingthere-with and forming the pipe to the predetermined bending radius andsize.

In accordance with the invention, a further set of rollers comprising abending roller 2b and a calibrating roller 3a are mounted on a holder 5which, in turn, is pivotally mounted on a pivot pin or shaft 10. Inorder to permit the pivotal movement, the magazine is recessed as at 1d.

The magazine 1 may be slid backwardly and forwardly by a drivingmechanism (not shown) which is operative through a connecting rod 14 toeffect the desired movement backwardly and forwardly in the directionsof the double arrows 16. This selected backward or forward movement forpositioning the bending elements in proper relation to the pipe beingbent is also eflective to shift the roller set comprising the rollers 2band 3a on the holder 5. This shifting is accomplished by moving a lever6 secured to the holder 5 to rotate the holder 5 about its pivot 1c inaccordance with the amount with which a roller follower 6a is shifted bya cam slot 8a on a cam member 8 which is secured to the frame 4. The camslot 8a is advantageously made of U-shaped configuration and the roller6a of the lever 6 is confined therein for move ment therealong. Theroller 7 moves along the curved track of guide rail 8 as determined bythe cam slot 8a and sets the rolls 2b and 3a of the roll unit to therespective desired or required pipe bending radius during the shiftingof the magazine.

With the arrangement of the invention, it is possible to move themagazine carriage 1a along the entire width of the winding cage (notrepresented). The curved track member 8 with its associated slot 8acontrols the holder 5 with the cooperative rollers 21) and 3a so thatthe radius for the pipe to be bent will correspond to the carriageposition. Such an arrangement permits the winding of the pipe into coilswhich may be exactly superposed in spiral layers.

Rollers such as rollers 2 and 2a are advantageously driven by a drivingmechanism (not shown) which is carried on the frame above the magazine1.

What is claimed is:

1. A bending device particularly for bending hot-rolled pipes which areto be subsequently wound on a device such as a reel, comprising amounting base, a magazine movable backwardly and forwardly along saidmounting base, said magazine having at least one stationary bendingroller and one calibrating roller adjacent the entrance end thereof, aholder pivotally mounted on said magazine and carrying a bending andcalibrating roller arranged in a cooperative roller set between whichthe pipe to be bent is adapted to be passed, and means connected betweensaid holder and said mounting stand for shifting said holder inaccordance with the movement of said magazine along said mounting stand.

2. A device, according to claim 1, wherein said holder is pivotallymounted on said magazine, a lever connected to said holder for shiftingsaid holder about its pivotal mounting, said lever having a followerportion, and a member carried on said frame and having a slot camdefined therein engaged with said follower portion of said lever andcomprising said means for shifting said holder during movement of saidmagazine relative to said stand.

3. A device, according to claim 2, wherein said cam follower on saidlever comprises a roller engaged in said slot.

4. A device, according to claim 3, wherein said member comprises a guiderail detachably connected to said frame.

5. A device, according to claim 4, wherein said guide rail extends alongthe length of said frame.

6. A device, according to claim 5, including a bending roller arrangedat the entrance of said magazine, a hopper guide disposed between saidfirst bending roller and said cooperative bending roller and calibratingroller on said magazine.

References Cited UNITED STATES PATENTS 551,827 12/1895 Litchfield72-l75X 2,467,671 4/1949 Hulburt et al 72175 MILTON C. MEHR, PrimaryExaminer

